On Tue, Apr 02, 2024 at 05:20:43PM -0700, Mina Almasry wrote: > Abstrace the memory type from the page_pool so we can later add support > for new memory types. Convert the page_pool to use the new netmem type > abstraction, rather than use struct page directly. > > As of this patch the netmem type is a no-op abstraction: it's always a > struct page underneath. All the page pool internals are converted to > use struct netmem instead of struct page, and the page pool now exports > 2 APIs: > > 1. The existing struct page API. > 2. The new struct netmem API. > > Keeping the existing API is transitional; we do not want to refactor all > the current drivers using the page pool at once. > > The netmem abstraction is currently a no-op. The page_pool uses > page_to_netmem() to convert allocated pages to netmem, and uses > netmem_to_page() to convert the netmem back to pages to pass to mm APIs, > > Follow up patches to this series add non-paged netmem support to the > page_pool. This change is factored out on its own to limit the code > churn to this 1 patch, for ease of code review. > > Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx> ... > diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helpers.h ... > @@ -170,9 +172,10 @@ static inline void *page_pool_alloc_va(struct page_pool *pool, > struct page *page; > > /* Mask off __GFP_HIGHMEM to ensure we can use page_address() */ > - page = page_pool_alloc(pool, &offset, size, gfp & ~__GFP_HIGHMEM); > + page = netmem_to_page( > + page_pool_alloc(pool, &offset, size, gfp & ~__GFP_HIGHMEM)); > if (unlikely(!page)) > - return NULL; > + return 0; Hi Mina, This doesn't seem right, as the return type is a pointer rather than an integer. Flagged by Sparse. > > return page_address(page) + offset; > }